81384374668 has 24 divisors (see below), whose sum is σ = 149289330960. Its totient is φ = 38776442880.

The previous prime is 81384374597. The next prime is 81384374671. The reversal of 81384374668 is 86647348318.

It is a super-2 number, since 2×81384374668² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5763253 + ... + 5777356.

It is an arithmetic number, because the mean of its divisors is an integer number (6220388790).

Almost surely, 2^81384374668 is an apocalyptic number.

It is an amenable number.

81384374668 is a deficient number, since it is larger than the sum of its proper divisors (67904956292).

81384374668 is a wasteful number, since it uses less digits than its factorization.

81384374668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11540697 (or 11540695 counting only the distinct ones).

The product of its digits is 18579456, while the sum is 58.

The spelling of 81384374668 in words is "eighty-one billion, three hundred eighty-four million, three hundred seventy-four thousand, six hundred sixty-eight".